While the Arduino UNO and Arduino Mega is “enough” for most projects,
sometimes you need something more powerfull … In my case, I always grab an ESP32.
Let’s begin with a comparison, ESP32 has a much more powerfull microcontroller
AND has much more memory (and even has WIFI and Bluetooth onboard)
So, with these ESP32 modules, you can even control full-color TFT screens ! (see my project with the ESP32-Cam)
Comparison table
| ESP32 NodeMCU | ESP8266 WeMos D1 Mini | Arduino NANO 3 | Arduino UNO R3 | Arduino Mega | |
| Microcontroller | ESP32 | ESP8266 | ATmega328p | ATmega328p | ATmega2560 |
| Operating Voltage | 3.3V | 3.3V | 5V | 5V | 5V |
| Power supply | 7V – 12V | 4V – 6V | 7V – 12V | 7V – 12V | 7V – 12V |
| Current consumption | 20 – 240 mA | 19 – 180 mA | 45 – 80 mA | 50 – 200 mA | |
| Current consumption Deep Sleep | 5 µA | 23 µA | 35 mA | 500 µA | |
| Digital I/O Pins | 36 | 11 | 14 | 14 | 54 |
| Digital I/O Pins with PWM | 36 | 11 | 6 | 6 | 15 |
| Analog Input Pins | 15 | 1 | 8 | 6 | 16 |
| SPI / I2C / I2S / UART | 4 / 2 / 2 / 2 | 1 / 1 / 1 / 1 | 1 / 1 / 1 / 1 | 1 / 1 / 1 / 1 | 1 / 1 / 1 / 4 |
| DC Current per I/O Pin | 20 mA | 40 mA | 40 mA | 20 mA | |
| DC Current for 3.3V Pin | 40 mA | 50 mA | 150 mA | 150 mA | |
| Flash Memory | 4 MB | 4 MB | 32 KB | 32 KB | 256 KB |
| SRAM | 520 KB | 2 KB | 2 KB | 8 KB | |
| EEPROM | – | 1024 bytes | 1024 bytes | 4096 bytes | |
| Clock Speed | 80 / 160 Mhz | 80 / 160 Mhz | 16 Mhz | 16 Mhz | 16 Mhz |
| Length | 52 mm | 34 mm | 45 mm | 69 mm | 102 mm |
| Width | 31 mm | 26 mm | 18 mm | 53 mm | 53 mm |
| WIFI | yes | yes | no | no | no |
| Bluetooth | yes | no | no | no | no |
| Touch sensor | 10 | no | no | no | no |
| CAN | yes | no | no | no | no |
| Ethernet MAC Interface | yes | no | no | no | no |
| Temperature Sensor | yes | no | no | no | no |
| Hall effect sensor | yes | no | no | no | no |
| Power jack | no | no | no | yes | yes |
| USB connection | yes | yes | yes | yes | yes |
Because the ESP32 works a bit different then Arduino UNO or Arduino Mega, you need a different Loconet library.
You can download the ESP32 Loconet library here.